The man, who The Courier can not identify because of the familial link to the victim, pleaded not guilty to three counts of indecent assault and one charge of gross indecency. He appeared in court on Wednesday.

The victim, now in her 40s, told the court she was under the age of 10 when she alleges the offending first occurred.

Crown prosecutor Andrew Grant told the court in the woman's testimony, which had previously been presented in a closed session, that she was sitting in the back seat during a car trip to an Avoca camp from Ballarat with family members in around 1988.

The accused was driving, and the woman alleges he put his arm behind the seat and "grabbed her knee" so she "knew what he wanted" her to do, before he pulled her arm back around and had her masturbate him under a rag. "It's pretty clear in my submission it is a period of time when it's dark in the car, everyone is asleep, they're getting close to the camp site, he grabs her hand ... then places the rag of the top of his lap as the act was occurring," Mr Grant said.

The crown prosecutor said while the accused man claimed he'd only driven the girl to a campsite once, which was in north-west Victoria, witness testimony from his ex-wife stating he had driven the victim to multiple camps contradicted the statement he gave to police.

"You simply couldn't accept him as a person giving an account you can rely upon," Mr Grant said.

The jury was told the accused had previously pleaded guilty to sexual offences against his own daughter.

Defence lawyer David Cronin said the woman's testimony about the car trip "borders on the ridiculous" as his then-wife was in the car and would have been woken up during the alleged act, and the man would have had obvious sexual stains on him.

He said the victim had a history of dishonesty offences from 1999 to 2015, including obtain property by deception and burglary, and had admitted to "drinking to blackout" and taking illicit drugs when she gave her first statement to police in 2014.

"You should have hackles raised at the back of your neck to be prepared to accept what she said," Mr Cronin told the 12-person jury.

He said his client had openly admitted to assaulting his daughter, but the current complaint was part of a conspiracy to destroy him.

"(His police interview) is entirely consistent with someone telling the truth, he's not clamming up, he's doing his best to answer questions," Mr Cronin said.

The jury will continue deliberations on Thursday.

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